How do you remove something based off a rank?

Hello!

I have this script, which deletes a button and frame inside the GUI if the person is either:

1. Not high enough rank OR
2. Is a high enough rank, but does not have permission to click on the button.

I want this to work so that when a player resets, it still works and this is why I've put this script inside StarterPark.

plr = script.Parent.Parent.Name
local b = plr:GetRankInGroup(1096916)
    if b == 200 then
        script.Handbook.Frame.Menu.DTProc:Destroy()
        script.Handbook.Frame.DTTrainProc:Destroy()
    end

    if plr.GetRankInGroup(1096916) < 150 then
        script.Handbook.Frame.Menu.DTProc:Destroy()
        script.Handbook.Frame.DTTrainProc:Destroy()
    end



local a = script.Handbook:Clone()
a.Parent = script.Parent.Parent.PlayerGui

script:Destroy()

However, when this does run I get some sort of nil value error. Anyone know what's this about?

EDIT: The error is:

01:36:01.711 - Players.Player.Backpack.Script:4: attempt to call method 'GetRankInGroup' (a nil value)